An experiment is underway to determine if the selective estrogen receptor modulators, called raloxifen and SERM 3, alter gene expression in serotonin neurons in the same manner as natural estrogen. Monkeys are spayed and then treated for one month with vehicle, estrogen, raloxifen, or SERM3 at 5 mg/kg/day orally. After treatment, the monkeys are euthanized and the midbrain is obtained for determination of expression of the serotonin reuptake transporter gene and the 5HT1A autoreceptor gene. FUNDING Eli Lilly Pharmaceutical Co. PUBLICATIONS None